<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title></title>
	</head>
	<body>
		<script>
			//ES5方式
			function fn(name, age){
				name = name \\ "tom";
				age = age \\ 17;
				console.log(name + "." + age);
			}
			//ES5 + 类型检查
			function fn2(name, age){
				name = (typeof name != 'undefined'? name: 'tom');
				name = (typeof age !='undefined'? age: 17);
				console.log(name + "." + age);
			}
			//ES6方式
			function fn3(name='tom'; age=17){
				console.log(name + "." +age);
			}
			
			fn();
			fn2();
			fn3();
			乡新有没有赋值，女

		</script>
		
	</body>
</html>
